Display of an artwork is a constantly evolving process which is greatly influenced by the artist's creativity, imagination, presenting medium, and the technology available. Different modes for display of indicia and/or images have conventionally been used. For example, certain art forms, created or reproduced on a medium such as planar devices display different images when viewed from different angles. In another example, the use of venetian blind type of devices for alternately hiding or revealing a picture is well known in the field of children's books or amusement devices.
Different types of optical illusions have been employed by a variety of artists including painters, sculptors and photographers for creating a mystery or surprise effect, especially to the viewers or audience. Changing the depth of view constitutes a form of optical illusion which reveals a complete image or structure with a pleasant and surprising perception of depth, when the viewing angle or viewing perspective of the observer is changed from one to another.